Synopsis

Kawai Haruto belongs to a cinema club to realize his dream to make his own movie. But he is losing his passion of the movie because Hina Yusuke, his best friend as well as a good rival, died suddenly last year. One day, he meets Sendo Mahiro. She asks him to make a movie with her. Also she says that she was at the place where Yusuke died, and that he died because of her. On the other hand, Yusuke’s little sister Hina Asuka blames him for killing her brother.

You actually have to read the synopsis to get what's going on, as nothing of it is explained in the OVA itself.

Shortly put, the story is about a girl which is somehow being blamed for the death of some dude. Therefore, she thinks of herself as a horrible person who should be with nobody and cuts all ties with her friends. In the end, they find her and they reunite. The End.
It is unclear how that person died, or who that person was for that matter, how she is to blame for that, and how that person (or
the girl) is related to the other main character(s). Even for a single short OVA, it leaves a lot of open questions and vagueness. On top of that, it's quite boring.